Above, Maeve Mangine poses for a photo with a log full of shiitake mushrooms in Shrewsbury. Below, a water tank used to grow shitake mushrooms is displayed.

SHREWSBURY — Lucas Jackson and Maeve Mangine shifted plans for a farm centered on a goat dairy after taking a workshop in growing shiitake mushrooms. All it took was logs from their land, mushroom spawn and their labor.

Now they’re selling the spongy rich mushrooms to several Vermont restaurants and a food cooperative and through a community supported agriculture farm. This season, they expect to produce about 500 pounds of mushrooms, which retail for as much as $16 a pound.

The couple’s Tangled Roots Farm in Shrewsbury is one of about 20 farms chosen in Vermont and New York as research sites under a $116,000 U.S. Department of Agriculture grant provided to the University of Vermont Extension’s Center for Sustainable Agriculture and Cornell University Cooperative Extension in 2010.

A UVM-Cornell study conducted over the last three years under the grant has found that growing mushrooms outdoors can be profitable to farmers with at least 500 logs, bringing in $11,190 in gross income at $16 a pound, and that demand is outstripping supply.

Next month, the universities plan to complete a guide for growing shiitake mushrooms in the Northeast.

Jackson, 27, and Mangine, 28, were among 500 to 600 people who attended a series of workshops held by the universities to teach Northeast farmers how to grow shiitakes while using resources from managing or thinning their land and forests.

Like other Northeast farmers, they’re limited by the cold, unlike larger-scale operations in Pennsylvania where mushrooms are grown indoors on compressed sawdust logs in controlled environments. But what they do have going for them is little, if any, overhead: the hardwood logs, a shady spot in the woods, water from a spring up the hill and a refrigerator to store the freshly harvested shiitakes.

“The average temperature needs to be above 40-ish, so we’re pretty limited in our outdoor fruiting season in Vermont and that’s kind of the nature of what we’re doing,” said Mangine, who works as a school administrator. “But growing them outside like this is really nice because we really have very few inputs.”

The Tangled Roots Farm, one of the larger in Vermont, has grown to 500 logs. Each log produces about half a pound of mushrooms twice a season.

Through the USDA grant, the farm received shiitake spawn, which is inserted into holes drilled into the roughly 3-foot logs.

The holes are sealed with wax and the logs sit for a year in stacks while the spawn colonizes the wood. A year later, farmers shock the logs by immersing them in a tub of water, which stimulates them to grow shiitakes. The logs are then removed from the water and stacked, and the shitakes grow within a week to 10 days.

A fresh shiitake torn off one of their sugar maple logs is both light and meaty, with a rich nutty flavor featuring a hint of garlic.

“They’ve just got a load of different flavors for different people,” Jackson said.

And nutritional benefits to boot. Mushrooms provide nutrients such as potassium, Vitamin D, selenium and riboflavin.

Demand for mushrooms is inching up, said Laura Phelps, president of the American Mushroom Institute, a trade organization representing indoor mushroom growers.

Per capita consumption is about 4 pounds per person per year now in the U.S., up from 3.6 pounds two years ago and 1.9 pounds in 1975, she said.

Shiitakes are just a tiny fraction of the 896 million pounds of fungi produced in the U.S. from 2012 to 2013. The U.S. crop is mostly Agaricus mushrooms, such as the common white button mushrooms and brown mushrooms, including portobello and cremini varieties, which are commonly grown indoors.

The number of commercial shiitake growers who have at least 200 logs in production or a commercial indoor growing area has grown from 142 producing 7.7 million pounds from 2003 to 2004 to 179 producing 8.6 million pounds from 2012 to 2013, according to the USDA National Agriculture Statistics Service.

Julie Rockcastle and her husband, Steve, owners of Green Heron Growers in Sherman, N.Y., served as advisers to the UVM-Cornell project. They got into shiitake growing in 2007 at the urging of their son, a Cornell University student who was friends with the president of the mushroom club there.

“They showed us an area in our hemlock woods that would be perfect for shiitake production, and they helped get us started,” said Julie Rockcastle.

Like Tangled Roots Farm, which also sells raw goats’ milk and chicken, Green Heron Growers doesn’t just focus on mushrooms. It’s just one of their farm ventures, along with organic vegetables, chickens, eggs and grass-fed beef, but it’s one of their most popular.

“There’s pretty high demand,” she said. “We go to the farmers market in Buffalo and never have enough.”

The study found anecdotedly that demand for these forest-grown shiitakes far outstrips supply, said Ben Waterman, who serves as outreach coordinator for the project.

“We could see eight times the current production and still maintain pricing at $16 a pound retail. So there’s a lot of room for new growers to get into this,” he said.

Encouraged by their success, the Rockcastles enlist volunteers each spring to prepare the logs in an effort to increase production to meet demand. Like Tangled Roots, they’re also trying other mushroom varieties, including lion’s mane and maitake.

“It’s a wonderful product for a farm that has other things going on,” Rockcastle said.